OEM Carrier Transformer 40VA 120V to 24V for Model FA4CNF036008AAAA

This is the factory OEM replacement transformer (part number HT01CN241) for the Carrier FA4CNF036008AAAA air handler. The transformer is the heartbeat of your system's control circuit — it steps down 120V line voltage to the 24V signal voltage that powers your thermostat, control board, contactor coil, and zone controls. When it fails, nothing responds: the thermostat goes blank, the system refuses to call for heating or cooling, and no error codes appear because the control circuit itself has lost power.

• Specs: 40VA rating | 120V primary / 24V secondary | Single-phase | Matches factory wiring harness and mounting footprint for the FA4CNF036008AAAA air handler
• OEM vs Generic: The OEM HT01CN241 transformer is wound to Carrier's exact VA rating and insulation class, ensuring stable 24V output under full control-circuit load. Undersized or off-brand units can sag voltage under load, causing erratic board behavior and nuisance lockouts.
• Install difficulty: 2/5 — Shut off all power at the breaker before beginning. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, multimeter (to confirm 24V output after install). Photograph existing wiring before disconnecting. Primary and secondary leads are color-coded for straightforward reinstallation.
• Warranty: 1-year OEM factory warranty. Orders placed before cut-off ship same business day from our warehouse.

Compatibility: Designed specifically for the Carrier FA4CNF036008AAAA fan coil/air handler. Verify your existing transformer's VA rating and input/output voltages on the unit's data plate before ordering to confirm fitment. Have questions about fit? Our HVAC parts specialists verify compatibility before you buy — just reach out.